Form and function
No fossils exist of other members of the Dugongidae. Stomach is a sac- like structure. But multi cellular serous glands are present. Young koalas are carried in the pouch for nearly 8 months, kangaroos to 10 months. Facts matter and Britannica Insights makes it easier to find them. Thus, the head functions in sensory reception , food acquisition, defense, respiration, and in higher groups communication. Sterling Pub Co Inc.
Mammals have live birth and care for their young for quite a time after birth. A mammal gas kidneys and is covered with skin. The skin has hair. Mammals are warm blooded. A mammal has bilateral symmetry. A mammal can be various shades of brown, black, tan, white. Protozoa - One Celled Animals. In most places drinking water can originate from different sources, hence the risk of pollution caused by nearby anthropogenic activities and natural rock erosion.
On small islets and islands of the Aegean, where the water resources are limited and potable water is transported to people via water tankers, the quality of the water can differ with each shipment delivered. The Archipelagos laboratory provides local island communities with water quality analyses in order to ensure that they have free, safe access to drinking water.
In addition, Archipelagos tests the water in regions where the contamination of groundwater is possible. When sources of pollution are detected, Archipelagos collaborates with local, national and EU authorities in order to eliminate them.
The Archipelagos laboratory supplies data on swimming water quality at various beaches and informs local authorities, communities and visitors whether the waters are safe for them and their children to swim in or not. In many places around the Greek coastline, such samples are not regularly collected by the national authorities.
Even when these tests are conducted, the results are not shared with the local communities. Our chemical water analyses are carried out using the photometric method certification ISO Growing healthy and productive crops requires good soil quality.
If your soil is poor, you can selectively add the nutrient that is lacking from your soil for the specific crop you are growing in place of adding chemical fertilizers. On the basis of this principle, the Archipelagos laboratory team offers free analyses of soil quality for farmers who are also advised of the nutrient content of their soil and of natural methods of replenishing any nutrients that are missing.
Our laboratory provides analyses of soil samples for the following parameters: Ammonia, calcium, chloride, free chlorine, cooper, iron, pH, magnesium, manganese, nitrate, nitrite, phosphate, phosphorus.
Archipelagos conducts research on pesticide residues in order to assess environmental effects of the use of pesticides and herbicides in farming practices and to inform consumers and farmers about these effects.
Using the results of our analyses, we create awareness campaigns that explain the health hazards of pesticides and encourage farmers to choose organic methods in place of chemical agents. Our laboratory team collects samples from olive groves, vineyards, vegetable gardens and greenhouses. Samples are collected and analyzed from the main crops, the produced goods e. In recent years there has been a slow but steady shift towards organic farming by people who live on the islands. Nevertheless, a lot of work is still needed for progress to be made on a large scale.
Our media and public relations team creates posters, leaflets, animations and documentaries as well as uses social media in order to ensure our success. Working closely with Archipelagos researchers and volunteers, the team shows the unique nature of the Aegean Sea and islands to the world.
The media and public relations team creates material on biodiversity, environmental conservation and public health issues through various platforms, with the goal of raising awareness and effecting change. Focusing on various subjects, interns take part in a range of projects, collaborating with different scientific teams.
The main fields of activity include: Focusing on illustrations of marine and terrestrial biodiversity in the Eastern Aegean Islands, interns have the opportunity to partake in different conservation-based projects.
By sketching from marine and terrestrial wildlife observations and pre-collected objects, they are merging photographic images with the knowledge of scientists. In addition, the interns create illustrations that are used in projects and campaigns that aim to raise public awareness of environmental issues.
As a result, they contribute to the environmental conservation efforts of Archipelagos while developing dynamic personal portfolios. Informational graphics and animations are crucial towards the success of environmental conservation efforts carried out by Archipelagos. Innovative visual material designed by the graphic and animation team focuses on a wide range of wildlife and conservation issues and is used in environmental awareness campaigns and educational material through a variety of media.
The conservation efforts of Archipelagos Institute can only be successful when shared with the local communities and the general public. In this regard, photography is an invaluable tool in depicting the biodiversity of the Aegean Islands, as well as the activities carried out by the Institute. Focusing on various subjects, photography interns take part in a range of projects, collaborating with different scientific teams. In this regard, documentary videos and films are invaluable tools in depicting the biodiversity of the Aegean, as well as local and global environmental issues.
The films are created for various purposes, including awareness videos for children and the general public, as well as for media TV and social media. Geo-information is a key tool in providing answers to complex issues concerning the conservation of our environment, as spatial analysis provides a better understanding of habitats and species.
In order to achieve effective environmental preservation in the Eastern Aegean Islands, habitats e. Through marine and terrestrial surveys, Archipelagos GIS interns collect various spatial data which is then assessed with the purpose of presenting distribution models e.
Current and future GIS projects include: Energy demand is constantly increasing in the whole world and Greece is not an exception. Archipelagos is developing projects which involve experimentation and application of small-scale renewable energy sources. Such solutions are low cost, sustainable and beneficial to the environment and the island communities. The aim is to examine efficient and inefficient examples of renewable energy sources and develop an optimal proposal which could be successfully applied on small scale across the Greek islands.
The work involved in this area includes:. Archipelagos also runs a number of websites, such as the wildlife library, which need to be continually maintained and updated. The placement focuses on database design and data mining, general system administration as well as creating new websites.
Projects may involve the following:. This knowledge is required to combat environmental crimes and to implement our management and conservation strategies of the environment.
Some of the work involved may include research and legal analysis related to:. At Archipelagos we are always in need of assistance to help with office organization and other relevant tasks. For almost two decades, Archipelagos has been offering environmental education lessons to schools and communities of the eastern Aegean islands.
It is a non-profit contribution from the researchers working at Archipelagos, but also the biggest investment that can be done to ensure the development of critical thinking and environmental awareness of the younger generation. Environmental education and awareness raising activities are tailored to address various target groups, in the numerous islands where Archipelagos is active.
The aim of these activities is the engagement of the local communities in several aspects of marine and terrestrial conservation and sustainability, including wildlife conservation, awareness of microplastics in the environment, and protection of the natural environment.
A minimum duration of 3 months is highly recommended for all participants, although shorter placements can be tailored to the needs of groups and individuals. Placements can last as long as 12 months. Placements may also include working on board of one of our research boats. Undergraduates and recent graduates of various courses related to biology, ecology, chemistry etc. Monthy fees of euro include: Start your career with a special experience!
Archipelagos Placement Guide Browse our Placement Guide with the latest internship opportunities in pdf version. The fields in which placements are offered: Study Area The monitoring of marine mammal populations focuses on the sea around Samos and extends to the islands of Ikaria, Fourni, Patmos, Arki and Lipsi.
Research surveys can focus on: Sea turtle populations, including green turtles and loggerhead turtles. Photo Identification During marine mammal pods sightings, the Archipelagos marine mammal team gathers photographic material used for identifying individuals inhabiting the studied area. Mediterranean Monk Seal Mediterranean monk seals are considered to be the second most endangered marine mammals in the world.
The Aegean Sea hosts some of the most important remaining marine mammal and sea turtle populations in the Mediterranean. Bad encounters between boats and mammals are common and can have disastrous con Underwater sounds caused by ships have no impact on humans, however, they may have severe effects on marine life, especially marine mammals.
Engine noise from boats increases with size, power, load and s Fisheries Fisheries have been an activity of vital importance to the island and Greek coastal communities for thousands of years. Coralligene Mapping Coralligenous reefs are frequently referred to as the best kept secret of the Mediterranean. Creating a map of coralligenous reefs in the eastern Aegean. Conducting biodiversity assessments of fish, invertebrates and algae, according to international protocols Collecting data on invasive species via underwater visual census surveys and questionnaires in order to understand the factors influencing the species distribution as well as the impacts on the ecosystem Creating GIS maps which provide an overview of species distribution Determining impacts of the factors threatening protected species and ecosystems using bio-indicator species Experimental installation of artificial reefs and sustainable mooring systems.
Shipping Risk Analysis The Mediterranean is considered to be of high risk for major spills from large cargo ships and tankers. Research in this field focuses on: Assessing and analyzing the shipping risk. Aquaculture Impacts The increasing demand for seafood, along with continued overfishing, have resulted in intensified aquaculture production in the Mediterranean. Work in this field includes: Analyzing the impact of aquaculture on coastal habitats and the accuracy of existing EIAs.
Collecting preliminary data to identify the impacts on biodiversity caused by different aquaculture practices and creating models of more sustainable approaches to aquaculture.
Cooperating with a medium sized aquaculture company on Leros island to modify its practices in order to create an eco-friendly model that respects the carrying capacity of the area. Eleonora Faraggiana, eleofara gmail. Introduction Microplastics are tiny pieces of plastics up to 5mm in size, anything bigger is considered a macroplastic. Since their invention in the s plastics have been polluting our oceans and waterways. Big pieces of plastic in the oceans are broken down by phytodegradation, photodegradation through plants or light or weathering processes Bat Research Bat research is conducted depending on qualifications e.
Behavioral response to adverse conditions may involve the selection or construction of a suitable microhabitat, such as the cool, moist burrows of desert rodents. Migration is a second kind of behavioral response.
The most obvious kind of mammalian migration is latitudinal. Many temperate-zone bats, for example, undertake extensive migrations, although other bat species hibernate near their summer foraging grounds in caves or other equable shelters during severe weather when insects are not available. Caribou Rangifer tarandus , or reindeer , migrate from the tundra to the forest edge in search of a suitable winter range, and a number of cetaceans whales , dolphins , and porpoises and pinnipeds walruses and seals undertake long migrations from polar waters to more temperate latitudes.
Gray whales , for example, migrate southward to calving grounds along the coasts of South Korea and Baja California from summer feeding grounds in the northern Pacific Ocean Okhotsk, Bering, and Chukchi seas.
Of comparable extent is the dispersive feeding migration of the northern fur seal Callorhinus ursinus. Migrations of lesser extent include the elevational movements from mountains to valleys of some ungulates—the American elk Cervus elaphus canadensis , or wapiti, and bighorn sheep Ovis canadensis , for example—and the local migrations of certain bats from summer roosts to hibernation sites.
Most migratory patterns of mammals are part of a recurrent annual cycle, but the irruptive sudden emigrations of lemmings and snowshoe hares are largely acyclic responses to population pressure on food supplies. The structure and dynamics of a population depend, among other things, on the relative lengths of these ages, the rate of recruitment of individuals either by birth or by immigration , and the rate of emigration or death.
The reproductive potential of some rodents is well known; some mice are reproductively mature at four weeks of age, have gestation periods of three weeks or less, and may experience postpartum estrus, with the result that pregnancy and lactation may overlap. Litter size, moreover, may average four or more, and breeding may occur throughout the year in favourable localities. The reproductive potential of a species is, of course, a theoretical maximum that is rarely met, inasmuch as, among other reasons, a given female typically does not reproduce throughout the year.
Growth of a population depends on the survival of individuals to reproductive age. The absolute age at sexual maturity ranges from less than 4 weeks in some rodents to some 15 years in the African bush elephant Loxodonta africana. Postreproductive individuals are rare in most mammalian populations.
Survival through more than a single reproductive season is probably uncommon in many small mammals, such as mice and shrews. Larger species typically have longer life spans than do smaller kinds, but some bats are known, on the basis of banding records, to live nearly 20 years. Many species show greater longevity in captivity than in the wild. Captive echidnas are reported to have lived more than 50 years.
Horses have been reported to live more than 60 years, and elephants have lived to more than Various cetaceans survive to more than 90 years of age, and research involving the dating of harpoons embedded in some Greenland right whales Balaena mysticetus , or bowheads, suggests that Greenland right whales can live years or more.
Specialization in habitat preference has been accompanied by locomotor adaptations. Terrestrial mammals have a number of modes of progression. The primitive mammalian stock walked plantigrade —that is, with the digits, bones of the midfoot, and parts of the ankle and wrist in contact with the ground.
The limbs of ambulatory mammals are typically mobile, capable of considerable rotation. Mammals modified for running are termed cursorial. The stance of cursorial species may be digitigrade the complete digits contacting the ground, as in dogs or unguligrade only tips of digits contacting the ground, as in horses.
In advanced groups limb movement is forward and backward in a single plane. This mode of locomotion is typically found in mammals living in open habitats.
Jumping mammals typically have elongate, plantigrade hind feet, reduced forelimbs, and long tails. Convergent evolution within a given adaptive mode has contributed to the ecological similarity of regional mammalian faunas. Bats are the only truly flying mammals. Only with active flight have the resources of the aerial habitat been successfully exploited.
Mammals belonging to other groups colugos , marsupials , rodents are adapted for gliding. A gliding habit is frequently accompanied by scansorial climbing locomotion. Many nongliders, such as tree squirrels , are also scansorial. Well-adapted arboreal mammals frequently are plantigrade, five-toed, and equipped with highly mobile limbs. Some species, including many New World monkeys , have a prehensile tail , which is used like a fifth hand. The primitive opposable anthropoid thumb is reduced as a specialization for this method of locomotion.
Tarsiers are highly arboreal primates that have expanded pads on the digits to improve grasping, whereas many other arboreal mammals have claws or well-developed nails. Several mammalian groups sirenians , cetaceans , and pinnipeds have independently assumed fully aquatic habits. In some cases semiaquatic mammals are relatively unmodified representatives of otherwise terrestrial groups otters , muskrats , and water shrews , for example.
Other kinds have undergone profound modification for natatorial swimming locomotion for life at sea. Pinniped carnivores walruses and seals give birth to their young on land, but cetaceans are completely helpless out of water, on which they depend for mechanical support and thermal insulation. The earliest mammals, like their reptilian ancestors, were active predators. From such a basal stock there has been a complex diversification radiation of trophic level adaptations.
Modern mammals occupy a wide spectrum of feeding niches. In most terrestrial and some aquatic communities, carnivorous mammals are the top predators. Herbaceous mammals often serve as primary consumers in most ecosystems. The voracious shrews , smallest of mammals, sometimes prey on vertebrates larger than themselves. They may eat twice their weight in food each day to maintain their active metabolism and compensate for heat loss caused by an unfavourable surface-to-volume ratio.
On the other hand, the largest of vertebrates, the blue whale Balaenoptera musculus , feeds on minute planktonic crustaceans called krill. Within a given lineage, the adaptive radiation of food habits may be broad. Some of the carnivores have become omnivorous raccoons , bears or herbivorous giant panda. In Australia the niche of large grazers and browsers is filled by a variety of kangaroos and wallabies. Within the bats there has also been a remarkable adaptive radiation of food habits.
Early in the history of the order, there evidently was a divergence into insectivorous insect-eating and frugivorous fruit-eating lines. The flying foxes Megachiroptera have generally maintained a fruit-eating habit, although some have become rather specialized nectar feeders. Members of the other major group Microchiroptera have been less conservative and have undergone considerable divergence in feeding habits. A majority of living microchiropterans are insectivorous, but members of two different families have become fish eaters.
Within the large Neotropical family Phyllostomatidae , there are groups specialized to feed on fruit , nectar, insects , and small vertebrates including other bats. Aberrant members of the family are the vampire bats , with a specialized dentition to aid blood lapping. We welcome suggested improvements to any of our articles. You can make it easier for us to review and, hopefully, publish your contribution by keeping a few points in mind.
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Please note that our editors may make some formatting changes or correct spelling or grammatical errors, and may also contact you if any clarifications are needed. Knox Jones David M. Page 1 of 3. Next page Form and function. Learn More in these related Britannica articles: At least 60 mammals have become extinct worldwide in the past two centuries, about a third of them from Caribbean islands. Of the remainder, 18 mammals were native to Australia, where they constituted about 6 percent of the terrestrial animal species prior to the….
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Nevertheless, several parallel changes occurred, such as the common incorporation of the sinus venosus into the right auricle. More About Mammal 68 references found in Britannica articles Assorted References annotated classification In vertebrate: Annotated classification characteristics of chordates In vertebrate: The tetrapods conservation and extinction issues In conservation: